Heat Dissipation Mechanism at Carbon Nanotube Junctions on Silicon Oxide Substrate

2014 ◽  
Vol 136 (5) ◽  
Author(s):  
Liang Chen ◽  
Satish Kumar

This study investigates heat dissipation at carbon nanotube (CNT) junctions supported on silicon dioxide substrate using molecular dynamics simulations. The temperature rise in a CNT (∼top CNT) not making direct contact with the oxide substrate but only supported by other CNTs (∼bottom CNT) is observed to be hundreds of degree higher compared with the CNTs well-contacted with the substrate at similar power densities. The analysis of spectral temperature decay of CNT-oxide system shows very fast intratube energy transfer in a CNT from high-frequency band to intermediate-frequency bands. The low frequency phonon band (0–5 THz) of top CNT shows two-stage energy relaxation which results from the efficient coupling of low frequency phonons in the CNT-oxide system and the blocking of direct transport of high- and intermediate-frequency phonons of top CNT to the oxide substrate by bottom CNT.

Author(s):  
Hua Bao ◽  
Shirui Luo ◽  
Ming Hu

Thermal transport across material interfaces is crucial for many engineering applications. For example, in microelectronics, small interfacial thermal resistance is desired to achieve efficient heat dissipation. Carbon nanotube (CNT) has extremely high thermal conductivity and can potentially serve as an efficient thermal interface material. However, heat dissipation through CNTs is limited by the large thermal resistance at the CNT-material interface. Here we have proposed a CNT-graphene junction structure to enhance the interfacial thermal transport. Non-equilibrium molecular dynamics simulations have been carried out to show that the thermal conductance can be significantly enhanced by adding a single graphene layer in between CNT and silicon. The mechanism of enhanced thermal transport is attributed to the efficient thermal transport between CNT and graphene and the good contact between graphene and silicon surface.


2021 ◽  
Author(s):  
Juhi Srivastava ◽  
Anshu Gaur

The phonon mode frequencies of SWNT and SLG in hybrid nanostructures are sensitive to various interactions, such as vdW forces, structural deformation and/or charge transfer between SWNT and SLG.


2021 ◽  
Vol 498 ◽  
pp. 115940
Author(s):  
Prashant Kumar ◽  
Rammohan Sriramdas ◽  
Ali E. Aliev ◽  
John B. Blottman ◽  
Nathanael K. Mayo ◽  
...  

Author(s):  
Amit Kumar Mondal ◽  
Vindhya Devalla ◽  
Vivek Kaundal ◽  
Kamal Bansal

This paper addresses a technique to solve the problem of heat dissipation in solenoid coil of the solenoid valve which is controlling the hydraulic damper by using pulse width modulation (PWM) switching technique with low frequency. In addition to this damper controlling is achieved via wireless controlling. By using PWM based low frequency switching technique the gas turbine trip will be protected. PWM is achieved by microcontroller and wireless control is done by ZigBee.


2011 ◽  
Vol 7 (S284) ◽  
pp. 411-413 ◽  
Author(s):  
David Sanchez ◽  
Berrie Giebels ◽  
Pascal Fortin ◽  

AbstractMatching the broad-band emission of active galaxies with the predictions of theoretical models can be used to derive constraints on the properties of the emitting region and to probe the physical processes involved. AP Librae is the third low frequency peaked BL Lac (LBL) detected at very high energy (VHE, E>100GeV) by an Atmospheric Cherenkov Telescope; most VHE BL Lacs (34 out of 39) belong to the high-frequency and intermediate-frequency BL Lac classes (HBL and IBL). LBL objects tend to have a higher luminosity with lower peak frequencies than HBLs or IBLs. The characterization of their time-averaged spectral energy distribution is challenging for emission models such as synchrotron self-Compton (SSC) models.


Langmuir ◽  
2008 ◽  
Vol 24 (11) ◽  
pp. 5903-5910 ◽  
Author(s):  
Ruslan Burtovyy ◽  
Igor Luzinov

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